In the past three decades, electricity has risen from 25% to 40% of end-use energy consumption in the United States. With this rising demand for power comes an increasingly critical requirement for highly reliable, high quality power. As power demands continue to grow, older urban electric power systems in particular are being pushed to the limit of performance, requiring new solutions.
Wire forms the basic building block of the world's electric power system, including transformers, transmission and distribution systems, and motors. The discovery of revolutionary high-temperature superconductor (HTS) compounds in 1986 led to the development of a radically new type of wire for the power industry; this discovery is the most fundamental advance in wire technology in more than a century.
HTS wire offers best-in-class performance, carrying over one hundred times more current than conventional copper and aluminum conductors of the same physical dimension do. The superior power density of HTS wire will enable a new generation of power industry technologies. It offers major size, weight, and efficiency benefits. HTS technologies will drive down costs and increase the capacity and reliability of electric power systems in a variety of ways.
For example, HTS wire is capable of transmitting two to five times more power through existing rights of way. This new cable will offer a powerful tool to improve the performance of power grids while reducing their environmental footprint. However, to date only short samples of the HTS tape used in the manufacture of next-generation HTS wires have been fabricated at high performance levels. In order for HTS technology to become commercially viable for use in the power generation and distribution industry, it will be necessary to develop techniques for continuous, high-throughput production of HTS tape.
One challenge facing the high-throughput production of HTS tape is the optimization of the buffer layers atop which the superconducting layer is deposited. Buffer layers are deposited atop a metal substrate, such as a stainless steel or nickel substrate, and are grown with preferential crystallographic texture so as to enable the optimum crystalline alignment of a subsequently deposited layer of HTS material, such as yttrium-barium-copper-oxide (YBCO). However, the elongated and non-symmetric YBCO unit cell has posed challenges to the growth of superconductor materials that utilize YBCO as a superconducting layer.
Budai et al., U.S. Pat. No. 5,968,877, dated Oct. 19, 1999 and entitled “High Temperature YBCO Superconductor Deposited on Biaxially Textured Ni Substrate,” provides a superconductor material that includes the buffer layers cerium oxide (CeO2) and yttrium-stabilized zirconia (YSZ), and a top layer of in-plane aligned, c-axis oriented YBCO that achieves a critical current density (Jc) in the range of 100,000 A/cm2 at 77 K. However, only short lengths of HTS tapes have been fabricated at such high performance levels. Further, the process of Budai et al. necessitates separate deposition processes occurring at different times to obtain the desired buffer layers.
The high throughput necessary to enable cost-effective production, and hence widespread adaptation of HTS materials, requires a system capable of simultaneous buffer layer deposition processes.
It is therefore an object of the invention to provide a deposition system for the production of HTS tapes that provides a first deposition process that subsequently feeds a second dynamically isolated deposition process such that the continuous sequential deposition of multiple thin films occurs.
It is an object of the invention to provide a high throughput deposition system utilizing two deposition zones in a single chamber.
It is an object of this invention to simultaneously subject a translating substrate to two different processes in a single deposition chamber.
It is an object of this invention to simultaneously subject a translating substrate to a deposition process and a coating modification process in a single deposition chamber.
It is an object of this invention to provide a multi-chamber modular coating line where the speed and conditions within each deposition chamber may be independently and easily modified without reconfiguring or disassembling the coating line.